Brain Lesions Nidus and Bruit what are the treatment options

Senior Neurosurgeons explain the difference between cerebral aneurisms and arteriovenous malformations (AVMs) and the types of treatments suggested by the Neurovascular Multi-Disciplinary Team.

Cerebral Aneurysms can arise from weaknesses (lesions) in the wall of the cerebral blood vessels. The cause of cerebral aneurysm formation is unknown, but most studies suggest that they occur in between 2% and 5% of the whole population. Unfortunately these weaknesses have a risk of rupture (“bursting”) and such an event has major implications.  Treatment of these lesions depends if they have ruptured or not. Ruptured aneurysms (SAH) are a medical emergency and immediate hospital admission and review by a consultant neurosurgeon is required. A CT scan of the head is sufficiently diagnostic in 99% of the cases, however, some patients may require further tests like a lumbar puncture to confirm that a rupture has occurred. The aim of early treatment is to support the patient and secure the aneurysm to protect from repeat bleeds.

Endovascular Coiling or Craniotomy

Treatment can be either through the arteries/veins (endovascular coiling) or through an open operation (craniotomy). The decision on the best mode of treatment is taken after special investigations have been performed and the patient reviewed by a neurosurgeon with a special interest in the treatment of aneurysms.

Arteriovenous Malformations (AVMs) and a 'Nidus'

As King’s College Consultant Neurosurgeon Mr Ranj Bhangoo explains, “Normally blood flows from the heart to the arteries of the body. The arteries branch and get smaller until they become a capillary, which is just a single cell thick. In this way blood pressure drops to very low levels that the thinner walled veins can cope with. In an arteriovenous malformation (AVM), usually early in life, arteries connect directly to veins. This is a high-pressure shunt or fistula. Veins are not able to handle the pressure of the blood coming directly from the arteries. The veins stretch and enlarge and create what we call a ‘nidus’.”

The symptoms of AVMs vary depending on their type and location. While migraine-like headaches and seizures are general symptoms, most AVMs do not show symptoms until a bleed occurs. Common signs of brain AVMs include the following:

  • sudden onset of a severe headache,
  • vomiting,
  • a stiff neck,
  • seizures,
  • migraine-like headaches or a
  • Bruit – a swishing sound in the ears

Surgery, endovascular therapy, and radiosurgery can be used alone or in combination to treat an AVM. Endovascular embolization is often performed before surgery to reduce the AVM size and risk of operative bleeding. Radiosurgery or embolization may be used after surgery to treat any remaining portions of the AVM. Your neurosurgeon will discuss with you all the options and recommend a treatment that is best for your individual case.

An abnormal swelling in the wall of an artery. Full medical glossary
A group of veins and arteries with abnormal connections between the two. Full medical glossary

An AVM or arteriovenous malformation forms when arteries connect directly to veins. This direct connection forms a high-pressure shunt or fistula. The veins are not able to handle the pressure of the blood coming directly from the arteries. The veins stretch and enlarge to create a “nidus”. Usually there are multiple feeding vessels in an AVM and many draining veins.

Full medical glossary

An AVM or arteriovenous malformation forms when arteries connect directly to veins. This direct connection forms a high-pressure shunt or fistula. The veins are not able to handle the pressure of the blood coming directly from the arteries. The veins stretch and enlarge to create a “nidus”. Usually there are multiple feeding vessels in an AVM and many draining veins.

Full medical glossary
A fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. Full medical glossary
The pressure of blood within the arteries. Full medical glossary
An abnormal swishing or ringing sound in the ear caused by blood pulsing through the AVM. Full medical glossary
The basic unit of all living organisms. Full medical glossary
Relating to the brain. Full medical glossary
Surgical removal of a part of the skull. Full medical glossary
The abbreviation for computed tomography, a scan that generates a series of cross-sectional x-ray images Full medical glossary
An abnormal channel between two parts of the body, for example between a hollow organ and another hollow organ, or between the inside and the outside of the body. Full medical glossary
The basic unit of genetic material carried on chromosomes. Full medical glossary
a general term to cover any abnormality such as a wound, infection, abscess or tumour. Full medical glossary
The part of the back between the lowest ribs and the top of the pelvis. Full medical glossary
A severe headache, often lasting 4 -72 hours and accompanied by visual disturbances, nausea and vomiting. Full medical glossary
septic arthritis Full medical glossary
Uncontrolled electrical activity within the brain, leading to convulsions or an alteration in mental state. Full medical glossary
Relating to blood vessels. Full medical glossary
A blood vessel that carries blood towards the heart. Full medical glossary
Relating to the veins. Full medical glossary
Expusion of the contents of the stomach through the mouth. Full medical glossary